Vibratory apparatus for working particulate solids

ABSTRACT

A vibratory apparatus for grinding, polishing, and doing similar work upon loosely disposed batches of mineral pebbles, a collection of geometrically similar metallic pieces, or other particulate solid substances. The vibratory apparatus comprises an elongate shelf member including a cantilever portion extending longitudinally from a stationary lateral node, a receptacle adapted to receive a batch of particulate solids and associated with the cantilever portion, means for rapidly twistably vibrating the cantilever as in alternating directions about the cantilever-axis at progressively decreasing amplitudes toward the node, and means for adjusting the amplitudes and frequencies of said twistable vibrations.

United States Patent [72] inventor Llo'yd E. Gaddy 1219 North Corona, Colorado Springs, Colo. 80903 [211 Appl. No. 54,321 [22] Filed July 13, 1970 [45] Patented Nov. 23, 197] [54] VIBRATORY APPARATUS FOR WORKING PARTICULATE SOLIDS l 1 Claims, 5 Drawing Figs.

[52] US. Cl 51/7, 51/163, 259/72 [51] Int. Cl B24b 31/06 [50] Field of Search 51/7, 163; 259/72 [56] References Cited UNITED STATES PATENTS 3,327,431 6/1967 Smith 51/7 Primary Examiner-Harold D. Whitehead Attorney-George R. Nimmer 51/163 UX 5l/7X ABSTRACT: A vibratory apparatus for grinding, polishing, and doing similar work upon loosely disposed batches of mineral pebbles, a collection of geometrically similar metallic pieces, or other particulate solid substances. The vibratory apparatus comprises an elongate shelf member including a cantilever portion extending longitudinally from a stationary lateral node, a receptacle adapted to receive a batch of particulate solids and associated with the cantilever portion, means for rapidly twistably vibrating the cantilever as in alternating directions about the cantilever-axis at progressively decreasing amplitudes toward the node, and means for adjusting the amplitudes and frequencies of said twistable vibratrons.

PATENTEDNUV 23 ISYI 3, 622.286

LLOYD E. 6400) INVENTOR.

ATTORNEY VIERATORI APPARATUS FOR W G ZARTZC'ULA'I'E SOLIDS The prior art teaches the general concept of grinding, smoothing, polishing, and doing similar work upon a loosely disposed collection of particulate solids by energizing said collection whereby the particles repeatedly frictionally engage one another. This general concept permits pebbles to be polished, metallic machined parts to be deburred, pulverizable material to be ground, paints to be compounded, etc. The most common examples of said general concept include cylindrical ball mills continuously revolvable about the longitudinal axis thereof, and uniformly supported multispring vibrators. However, ball mills require inordinately long periods of time to accomplish the desired work, are expensive to maintain and to clean, and are not amenable to variable control. The said multispring vibrators tend to require high capital and powering costs, are apt to become unevenly worn and misaligned over periods of use, and are not readily amenable to variable control.

It is accordingly the general object of the present invention to provide an efficient and economical apparatus for grinding. smoothing, polishing, and doing similar work upon a loosely disposed collection of particulate solids.

It is a more specific object to provide a vibratory apparatus for grinding, polishing, and performing similar work upon particulate solids, said apparatus being exceedingly reliable, and having relatively low power requirements.

It is another object to provide a vibratory apparatus that affords a versatile and adjustable permissible range of vibrational forces upon the particulate solids.

It is further object to provide a vibratory apparatus that permits efficient and rapid surface treatment of particulate solids, that is amenable to various size batches, and that does not require lengthy shutdown times for cleaning and maintenance.

With the above and other objects and advantages in view, which will become more apparent as this description proceeds, the vibratory apparatus generally comprises: a base member including a linearly laterally extending transversely protrusion; an elongate structurally continuous tridimensional shelf member extending laterally widthwise across said base member transverse-protrusion and linearly attached thereto whereby the shelf member has a laterally extending lineal node portion, said shelf member extending longitudinally lengthwise from and substantially perpendicular to the node portion whereby the shelf member has an elongate cantilever portion having its sole support along the shelf member node and having a free end remote of said node, said cantilever along the physical confines thereof including a longitudinally extending cantilever-axis, said cantilever along the entire free end thereof being resiliently twistable in both angular directions about the cantilever-axis with the degree of twistability decreasing progressively toward the said substantially stationary node; a receptacle associatable with the shelf member cantilever for removably receiving therein particulate solid material; and means for twistably vibrating the cantilever as in alternating angular directions about said cantilever-axis.

In the drawing, wherein like characters refer to like parts in the several views, and in which:

FIG. 1 is a perspective view of a representative embodiment of the vibratory apparatus of the present invention.

FIG. 2 is a sectional elevational view taken along line 2-2 of FIG. 1.

FIG. 3 is a detail top plan view of an adapter plate which might be employed to provide an adjustably positionable receptacle portion of the present invention.

FIGS. 4 and 5 are detail perspective views of the cantilever portion to schematically indicate the resilient twistability about the longitudinal cantilever-axis thereof, at decreasing amplitudes toward the substantially stationary node.

The representative embodiment D of the vibratory apparatus generally comprises a base member having a transverse-protrusion 18, a longitudinally extending shelf member stationarily attached along a laterally extending lineal node 21 to transverse-protrusion 18 whereby shelf member 20 includes a cantilever 29 having a longitudinally extending central cantilever-axis 29A, at least one receptacle, e.g. 40, surrounding a transverse-axis 40A and associated with the cantilever 29, and means such as revolvable weighty eccentric 52 for rapidly twistably vibrating cantilever 29 at a narrow transverse amplitude about the cantilever-axis to do physical work upon particulate solids 42 loosely disposed within receptacle 40.

Base member 10 herein comprises a longitudinally horizontally extending weighty plate 11 having a pair of laterally extending ends including a forward end 12 and a rearward end 13. Plate 11 has a pair of substantially parallel laterally separated longitudinal borders l4, and plate 11 has a pair of opposed transversely separated sides including an upper side 16 and a lower side 17. The base member 10 is stably associatable with respect to an appropriate anchoring means (as for example an underlying table top,) and in this vein, the longitudinally extending lower side 17 of rectangular plate 11 is a horizontally planar, there being a plurality of transverse perforations 15 in plate 11 for mounting fastener screws (not shown). Base member 10 includes a transverse-protrusion, herein as an upright block 18 extending transversely vertically upwardly from plate upper side 16, upright block 18 being attached to plate 11 as by a plurality of laterally aligned upright screws 99. Upright block 18 has a laterally extending planar horizontal surface 19 which provides an upper lofty terminus for base member 10, said lofty terminus being disposed transversely above plate rearward end 13 and remote of plate forward end 12.

Tridimensional elongate shelf member 20 is spaced a transverse distance above plate upper side 16, has a pair of substantially parallel laterally separated longitudinal edges 24, and has a laterally extending rearward end 23 perpendicularly intersecting said longitudinal edges 24. Shelf member 20 is provided as a longitudinally extending structurally continuous length of resiliently bendable material, such as metal, plywood, and the like, and in this vein herein, horizontal shelf member 20 is relatively thin in the transverse (herein vertical) direction, A rearward portion of shelf member 20 is attached to the base member transverse-protrusion 18 (along a linearly laterally extending node portion 21) as with a plurality of fastener bolts 97 extending vertically through shelf 20 and upright block 18. Thus, shelf member 20 along lineal node 21 is substantially stationary. The shelf member 20 herein has a pair of longitudinally extending parallel broad planar horizontal surfaces including an upper surface 26, and including a lower surface 27 continuously transversely separated from plate upper side 16 and abutting against said upright block at 19. Shelf 20 has an elongate forward lengthwise portion 29 extending longitudinally forwardly from and substantially perpendicular to stationary lineal nodal portion 21, said shelf forward portion 20 having a free forward end 22 intersecting both longitudinal edges 24.

It can be seen that the shelf forward portion 29, commencing rearwardly of its forward end 22, has its initial physical restraint along lineal nodal secure attachment 21, and thus, forward portion 29 is a cantilever having its sole support along node 21. Cantilever 29 along the physical confines thereof includes a longitudinally extending cantilever-axis 29A which is substantially perpendicular to lineal node 21. With the cantilever portion 29 herein having four intersecting borders (2], 23, and 24) and having a substantially regular transverse thickness between surfaces 26 and 27, the cantilever-axis 29A is continuously disposed between surfaces 26 and 27, and between edges 24. As is indicated in phantom line M of FIG. 2, cantilever 29 along its entire free end 22 thereof is transversely vertically resiliently deflectable.

Phantom lines NA and NB in FIGS. 2, 4, and 5 indicate schematically that the cantilever free end 22 is resiliently twistable in both angular directions about cantilever-axis 29A. As is more clearly shown in FIG. 2, the degree of twistability for cantilever 29 decreases progressively toward lineal node 2 l, at which there is substantially zero permissible movement. Phantom line NA of H05. 2 and 4% schematically indicates clockwise twisting while phantom line NB of H6. 3 similarly indicates counterclockwise twisting. Twisting motions NA and NB are separate and independent from the wholly vertical type motion M.

Preferably, there are means for selectively varying the length of the shelf member cantilever portion 29. For example, such length variation means might comprise longitudinally extending slots 28 through shelf member for passage of bolts 97. Wingnuts 98 threadedly engaged with bolts 97 and bearable against shelf upper surface 26 provide stationary node 21 and maintain the selected length of cantilever 29. The shelf member portion extending rearwardly of lineal node 21 to rearward end 23 provides a resonator 25.

There is at least one receptacle for solid material, said receptacle having an elongate transverse-axis A and the receptacle being associatable at a fixed relationship with the vibratory cantilever 29. Herein, the generally cylindrical receptacle 40 has a horizontal bottom 41, an upright sidewall circularly surrounding the receptacle vertical transverse-axis 40A, and an open top whereby mineral stones, metallic machine parts, or a similar particulate solid 42, might be placed within receptacle 43b. The receptacle, e.g. 430, is preferably removably (rather than permanently) associatable with the cantilever so as to permit the particulate load to be subjected to preparatory or subsequent treatments, e:.g. washing, etc, remote from vibratory apparatus D. Herein, such removable association is accomplished by temporarily mesting receptacle 4% into a geometrically similar container 40M The container 40N is relatively permanently attached to cantilever 29, as by weldably attaching same to an underlying horizontal adapter plate 45, said adapter plate 45 being attached to cantilever 29 as by vertical bolts 49 passing removably through members 45 and 29.

In the usual operational situation, the receptacle transverseaxis, e.g. 30A, would perpendicularly intersect cantilever-axis 29 very near cantilever free end 22, and with the entire receptacle positioned transversely remote of cantilever-axis 29A, all as shown in the drawing. However, for reasons to be explained later in greater detail, it is often times desireable that the receptacle be adjustably positioned (in the longitudinal, lateral, and transverse directions.) For example, as indicated in H68. 2 and 3, rectangular adapter plate 45 might have a plurality of -shaped (crosswise) transverse slots 46 for passage therethrough of fasteners 49, thereby providing one type means for selectively varying the longitudinal and lateral positions of receptacle 40. Moreover, one or more washers 47, transversely stacked between adapter plate 45 and cantilever 29 and each surrounding a bolt 49, might be employed as one type means for selectively varying the transverse position of the receptacle.

There are means for repeatedly vibrating the cantilever 29 as in alternating twisting directions about the cantilever-axis 29A, at a frequency exceeding 50 vibrational twists per minute, the said twistable vibrations being translated directly to the receptacle and to the particulate solids load therewithin. The twistable vibrations of cantilever Z9 progressively increase in transverse amplitude toward the cantilever free end 22, and the vibrations thereby translated to the receptacle transverse-axis progressively increase in lateral amplitude transversely away from cantilever-axis 29A. A variety of means might be employed for twistably vibrating the cantilever 29, such as make-and-break" electromagnetic devices, various mechanical linkages, and the like. However, the conventional electric motor 50 having an eccentric load 52 on its lineal revolvable shaft 51 provides an especially efficient, economical, and controllable, such vibrational means. Electrically actuatable motor 50 is attached to shelf member 20, as by bolts 59 transversely passing through the motors lower mounting plate and cantilever 29. As the lineal motor shaft 51 (which lies substantially parallel to cantilever-axis 29) continuously rotates about its elongate axis at a selected r.p.m

(for example, 1,700 r.p.m. the weighty corevolvable eccentric 52 causes substantially the same number of vibratory twists per minute, e.g. 1,700, in cantilever 29 and also a like number of laterally reciprocating motions to receptacle 40. If motor 50 be of the selectively variable speed type (as schematically indicated by element 54 in FIG. 2,) the frequency of the vibrational twists to cantilever 29 and the lateral vibrations upon associated receptacle 40 would be concomitantly varied.

For the usual operational situation, a shown in FIGS. 1 and 2, the motor shaft is disposed in that vertical plane extending transversely upwardly from cantilever-axis 29A, and eccentric 52 is located immediately rearwardly of receptacle 40 transversely above the receptacle bottom end 4i. However, for reasons to be explained later in greater detail, it is oftentimes desireable that the motor shaft eccentric 52 be adjustably positionable (in the longitudinal, lateral, and transverse directions.) For example, motors underlying horizontal mounting plate 55 (resting upon the cantilever upper surface 26) might have a plurality of -shaped transverse slots 56 for passage therethrough of fasteners 59, thereby providing one type means for selectively varying the longitudinal and lateral positions of eccentric 52. Moreover, one or more washers e.g. 47, transversely stacked between mounting plate 55 and cantilever upper surface 26, and each washer surrounding a bolt 59, might be employed as one type means for varying the transverse position of eccentric 52. If motor shaft 5! be sufficiently lengthy to overlie cantilever 29, motor 50 might be disposed rearwardly of node 21.

Operation of the vibratory apparatus D which has already been alluded to, will be summarized as follows. First, a batch of particulate solids 32, such as pebbles to be polished, is loosely loaded into receptacle 40 and receptacle 40 is associated with cantilever 29 as through container 40N. The open top of receptacle 40 might be covered provided with a removable cover (not shown) to protect the particulate solids 12 and any media utilized therewith (such as water). Then, the motor is actuated causing shaft 51 and associated eccentric 52 to revolve whereupon cantilever 29 is caused to rapidly twistably vibrate in alternating directions about cantilever-axis 29A, the transverse amplitude of said vibrations, e.g. NA, NB, being on the typical order of about one-fourth inch at cantilever free end 22 and decreasing progressively to substantially zero amplitude at stationary node 21. Receptacle 10 can be seen to vibrate laterally with the lateral amplitude increasing progressively along transverse-axis 40A away from cantilever 29. The vibrating particulate solids 42 frictionally rub against one another tending, for example, to reduce the solids surface area, e.g. to polish pebbles, etc. Close physical examination of the shelf member 20 reveals the resonator portion 25 (rearwardly of node 21) to be vibrating also. Vibrational amplitudes and the work performed upon the particulate solids can be selectively varied empirically by utilizing one or more of the following adjustable features: the longitudinal length of cantilever 29 can be varied through the slots 28 and wingnuts 98, the position for receptacle 40 can be varied in each of the three directions as through the slots 46 and the washers 47, and the position for revolvable eccentric 52 can be varied in each of the three directions as through slots 56 and similar washers 47 as aforedescribed. The apparatus herein is exceedingly rapid and efficient as compared to ball mills and related prior art grinding or polishing devices.

From the foregoing, the construction and operation of the vibratory device will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

I claim:

l. A vibratory apparatus for working particulate solid materials, said apparatus comprising:

A. A base member including a transverse-protrusion portion;

B. An elongate tridimensional shelf member extending longitudinally dimensionally lengthwise, extending laterally dimensionally widthwise, and being transversely relatively thin, said shelf member along a laterally extending lineal stationary node being attached to the base member transverse-protrusion whereby the shelf member includes a structurally continuous cantilever portion physically disposed along a longitudinally extending cantilever-axis that is substantially perpendicular to said stationary node, said shelf member cantilever portion terminating as a free end remote of said node, the cantilever portion being resiliently twistably deflectable in both angular directions about said cantilever-axis with the amplitude of said resilient twistability decreasing progressively from some finite value at the cantilever free end to substantially zero at the cantilever free end to substantially zero at the cantilever stationary node;

C. A receptacle for holding a batch of particulate solid material, said receptacle surrounding a transverse-axis and being associatable with the shelf member cantilever portion; and

D. Means for repeatedly twistably vibrating the shelf member cantilever portion at said decreasing amplitudes in alternating directions about said cantilever-axis at a vibrational frequency exceeding fifty twisting movements per minute whereby similar vibrational frequencies are transmitted to the particulate solids carried within said receptacle.

2. The vibratory apparatus of claim 1 wherein the longitudinal direction is substantially horizontal whereby the cantilever-axis extends horizontally longitudinally forwardly of the node to the cantilever free forward end; and wherein the transverse direction is vertical whereby the cantilever has a vertical thickness and the base member transverse-protrusion extends vertically upwardly toward the shelf member node.

3. The vibratory apparatus of claim 2 wherein the means for repeatedly twistably vibrating the shelf member cantilever portion comprises a powered revolvable shaft attached to the shelf member and carrying an eccentric weight corevolvable with said shaft.

4. The vibratory apparatus of claim 3 wherein the powered revolvable shaft is substantially parallel to the cantilever-axis; and wherein the eccentric weight carried thereby vertically overlies the shelf member cantilever portion.

5. The vibratory apparatus of claim 4 wherein the powered shaft is the revolvable shaft of an electrically actuatable variable speed motor attached to the shelf member; and wherein the position of the motor shaft is selectively laterally adjustable.

6. The vibratory apparatus of claim 5 wherein the receptacle vertical transverse-axis is disposed forwardly of the revolvable eccentric; and wherein the position of the motor shaft attached eccentric is selectively longitudinally variable.

7. The vibratory apparatus of claim 6 wherein the shelf member comprises two structurally continuous portions including the cantilever portion extending forwardly from the node and a resonator portion extending rearwardly from the node; and wherein the relative longitudinal length of the said two oppositely extending shelf member portions is selectively longitudinally adjustable.

8. The vibratory apparatus of claim 7 wherein the position of the receptacle is laterally, longitudinally, and vertically selectively adjustable; wherein the receptacle is removable associatable to the cantilever upper side through an underlying nesting support attached to the cantilever; and wherein there are means to controllably vary the revolving speed of said shaft.

9. The vibratory apparatus of claim 8 wherein the said shelf member comprises an elongate wood transverse thickness along the length of substantially parallel horizontal wherein the base member comprises a longitudinally horizontally extending plate located below and attached to the transverse-protrusion thereof wherebg said base member plate is located a finite vertical distance elow the shelf member cantilever portion, said base member plate being laterally wider than the shelf member and being vertically perforate for passage therethrough of fasteners appropriate to an underlying anchoring means.

it). The vibratory apparatus of claim 2 wherein the base member comprises a longitudinally extending plate located below and attached to the base transverse-protrusion, said base member being vertically perforate for passage therethrough of fasteners appropriate to an underlying anchoring means; wherein the shelf member comprises an elongate structurally continuous strip having a forward end, a rearward end, a pair of substantially parallel longitudinal edges, and a regular transverse thickness along the length thereof, said shelf member being provided with a least one longitudinal slot therethrough located nearer to the shelf member rearward end than to the forward end thereof, said shelf member being attached to the base member transverseprotrusion with mechanical fastener means extending downwardly through said elongate slotted portion whereby the longitudinal length of the cantilever portion can be selectively varied; wherein the means for repeatedly twistably vibrating the cantilever portion comprises an electrically actuatable motor attached to the shelf member and including an eccentric weight corevolvable with the motor shaft; and wherein the receptacle vertical transverse-axis is disposed forwardly of the revolvable eccentric, the receptacle being removable associatable with the cantilever at the upper side thereof through an underlying nesting support attached to the cantilever.

11. A vibratory apparatus for working particulate solid materials, said apparatus comprising:

A. A base member including a transverse-protrusion portron;

B. An elongate tridimensional shelf member extending longitudinally dimensionally lengthwise, extending laterally dimensionally widthwise, and being transversely relatively thin, said shelf member along a laterally extending lineal stationary node being attached to the base member transverse-protrusion whereby the shelf member includes a structurally continuous cantilever portion extending along a longitudinal cantilever-axis that is substantially perpendicular to said stationary node, said shelf member cantilever portion terminating as a free end remote of said node, the cantilever portion being resiliently deflectable with the amplitude of of said resilient deflectability decreasing progressively from some finite value at the cantilever free end to substantially zero at the cantilever stationary node;

C. A receptacle for holding a batch of particulate solid material, said receptacle surrounding a transverse-axis and being adjustably associatable with the cantilever at a selectable plurality of positions therealong; and

D. Means for repeatedly vibrating the shelf member cantilever portion at said decreasing amplitudes whereby vibrations are transmitted to the particulate solids carried within said receptacle, said vibratory means being adjustably positionable with respect to the cantilever stationary node portion whereby the vibrational characteristics of the cantilever and the associated receptacle can be selectively varied.

IF l

strip having a regular thereof and having a pair longitudinal edges; and 

2. The vibratory apparatus of claim 1 wherein the longitudinal direction is substantially horizontal whereby the cantilever-axis extends horizontally longitudinally forwardly of the node to the cantilever free forward end; and whErein the transverse direction is vertical whereby the cantilever has a vertical thickness and the base member transverse-protrusion extends vertically upwardly toward the shelf member node.
 3. The vibratory apparatus of claim 2 wherein the means for repeatedly twistably vibrating the shelf member cantilever portion comprises a powered revolvable shaft attached to the shelf member and carrying an eccentric weight corevolvable with said shaft.
 4. The vibratory apparatus of claim 3 wherein the powered revolvable shaft is substantially parallel to the cantilever-axis; and wherein the eccentric weight carried thereby vertically overlies the shelf member cantilever portion.
 5. The vibratory apparatus of claim 4 wherein the powered shaft is the revolvable shaft of an electrically actuatable variable speed motor attached to the shelf member; and wherein the position of the motor shaft is selectively laterally adjustable.
 6. The vibratory apparatus of claim 5 wherein the receptacle vertical transverse-axis is disposed forwardly of the revolvable eccentric; and wherein the position of the motor shaft attached eccentric is selectively longitudinally variable.
 7. The vibratory apparatus of claim 6 wherein the shelf member comprises two structurally continuous portions including the cantilever portion extending forwardly from the node and a resonator portion extending rearwardly from the node; and wherein the relative longitudinal length of the said two oppositely extending shelf member portions is selectively longitudinally adjustable.
 8. The vibratory apparatus of claim 7 wherein the position of the receptacle is laterally, longitudinally, and vertically selectively adjustable; wherein the receptacle is removable associatable to the cantilever upper side through an underlying nesting support attached to the cantilever; and wherein there are means to controllably vary the revolving speed of said shaft.
 9. The vibratory apparatus of claim 8 wherein the said shelf member comprises an elongate wood strip having a regular transverse thickness along the length thereof and having a pair of substantially parallel horizontal longitudinal edges; and wherein the base member comprises a longitudinally horizontally extending plate located below and attached to the transverse-protrusion thereof whereby said base member plate is located a finite vertical distance below the shelf member cantilever portion, said base member plate being laterally wider than the shelf member and being vertically perforate for passage therethrough of fasteners appropriate to an underlying anchoring means.
 10. The vibratory apparatus of claim 2 wherein the base member comprises a longitudinally extending plate located below and attached to the base transverse-protrusion, said base member being vertically perforate for passage therethrough of fasteners appropriate to an underlying anchoring means; wherein the shelf member comprises an elongate structurally continuous strip having a forward end, a rearward end, a pair of substantially parallel longitudinal edges, and a regular transverse thickness along the length thereof, said shelf member being provided with a least one longitudinal slot therethrough located nearer to the shelf member rearward end than to the forward end thereof, said shelf member being attached to the base member transverse-protrusion with mechanical fastener means extending downwardly through said elongate slotted portion whereby the longitudinal length of the cantilever portion can be selectively varied; wherein the means for repeatedly twistably vibrating the cantilever portion comprises an electrically actuatable motor attached to the shelf member and including an eccentric weight corevolvable with the motor shaft; and wherein the receptacle vertical transverse-axis is disposed forwardly of the revolvable eccentric, the receptacle being removable associatable with the cantilever at the upper side thereof through an underlying nesting support attached to the cantilever.
 11. A vibratory apparatus for working particulate solid materials, said apparatus comprising: A. A base member including a transverse-protrusion portion; B. An elongate tridimensional shelf member extending longitudinally dimensionally lengthwise, extending laterally dimensionally widthwise, and being transversely relatively thin, said shelf member along a laterally extending lineal stationary node being attached to the base member transverse-protrusion whereby the shelf member includes a structurally continuous cantilever portion extending along a longitudinal cantilever-axis that is substantially perpendicular to said stationary node, said shelf member cantilever portion terminating as a free end remote of said node, the cantilever portion being resiliently deflectable with the amplitude of of said resilient deflectability decreasing progressively from some finite value at the cantilever free end to substantially zero at the cantilever stationary node; C. A receptacle for holding a batch of particulate solid material, said receptacle surrounding a transverse-axis and being adjustably associatable with the cantilever at a selectable plurality of positions therealong; and D. Means for repeatedly vibrating the shelf member cantilever portion at said decreasing amplitudes whereby vibrations are transmitted to the particulate solids carried within said receptacle, said vibratory means being adjustably positionable with respect to the cantilever stationary node portion whereby the vibrational characteristics of the cantilever and the associated receptacle can be selectively varied. 